Lubricating apparatus



2 Sheets-Sheet l Aug. 19, 1947. E. w. DAvls LUBRICATING APPARATUS Filed Sept'. 20, .1945

Aug. 19, 1947. E. w. DAVIS LUBRICATING APP-ARATUS Filed sept. v2o, 1945 2 Sheets-Sheet 2 Patented'Aug. 19, 1947 UNITED STATES PATENT OFFICE LUBRICATING APPARATUS Ernest W. Davis, River Forest, Ill.

Application September Z0, 1945, Serial No. 617,545

8 Claims.

This invention relates generally to lubricant compressors, and more particularly to hand operated grease guns of the lever type.

One object of the invention`is to provide an improved grease gun, the operation of which will not be disadvantageously affected by the presence of air pockets. To attain this object, 'the invention provides means for intermittently packing the grease from the reservoir into the high pressure cylinder.

More specically, it is an object of the invention to provide mechanically actuated paddle or ilapper means operating in the vicinity of the port which connects the grease reservoir with the high pressure cylinder of a grease gun and actuating said means intermittently by the motion of the grease expelling piston for packing grease into the high pressure cylinder and eliminating air pockets therefrom.

Other objects of the invention will appear from the following description taken in connection With the accompanying drawings, in which:

Fig. 1 is a side elevational view of a grease gun embodying this invention With a portion of the structure shown in axial section;

Fig. 2 is a transverse sectional View taken as indicated at line 2 2 on Fig. 1;

Fig. 3 is a fragmentary vertical sectional view showing the invention in slightly modied form as applied to another type of grease gun;

Fig. 4 is a transverse sectional View taken as indicated at line 4--4 on Fig. 3.

The grease gun shown in Figs. 1 and 2 is of the portable hand operated type and includes a cylindrical reservoir I6 closed at one end by a cap I2 and at the other end by a cast head I4 into which the end of the cylinder I is threaded at I6. The head I4 is formed with a bore I8 which constitutes the high pressure cylinder and in which a piston or plunger 20 is reciprocable by means of a hand lever 22 fulcrumed at one end of the link 24 which is attached at its opposite end by a pivot 26 to a lug 28 on the head I4.

The high pressure cylinder I8 is fitted with a check valve 36 seated inwardly by a spring 32 and yielding to permit the discharge of grease through an outlet fitting 34 which may be connected with any suitable form of discharge terminal or conduit. The cylinder I8 communicates with the interior of the reservoir I6 by way of a port 36 in the head I4 and the grease in the reservoir is urged toward the port by means of a spring-pressed follower piston 38. A guide rod 40 is connected to the piston and extends through a central opening in the cap I2 and this rod is provided with a handle 42 which adapts the piston 38 to be drawn toward the cap I2 for filling the reservoir I6 With grease by suction, operating through an inlet tting 44 and passage 46. Features thus far described are conventional and need not be further elaborated.

In a device of this general type it sometimes happens that the mass of grease in the reservoir i6 develops voids or air pockets Which interfere With the steady discharge of grease from the cylinder I8. To prevent this, the present invention provides a paddle or flapper member 56 hingedly mounted at 52 andextending over and adjacent the port 36 so that it may swing toward and from the port about its hinge pivot. To actuate the flapper 56, a spring 54 is coiled about the hinge pivot 52 with one end of the spring engaged in a recess 56 in the head I4 and With the opposite end 58 engaging the flapper 50 at a short distance from the axis of the pivot 52. The spring thus urges the flapper toward the port 36; a pin 6I), slidably guided in the head I4, is disposed with one end engaging the frapper 56 and with its opposite end positioned to engage a cam surface 62 formed on the plunger 26 by cutting away a portion of the plunger and inclining the bottom of the cut with respect to the axis of the plunger. The cam surface 62 is so positioned that it actuates the pin 66 to swing the ilapper 50 away from 'the port 36 during the working stroke of the plunger by which it feeds grease from the cylinder I8 through the outlet 34. Then, on the return stroke of the plunger and as it uncovers the port 36, the cam 62 permits the spring 54 to swing the ilapper 50 toward the port 36 so as to force and pack the grease through the port and into the cylinder I8 ready for the next feeding stroke. This packing action of the flapper 50 applies pressure to the grease which operates to break down the walls of any voids and to collapse any air pockets therein, dispersing the air and forming the grease into a homogeneous mass in the cylinder I8.

The effectiveness of the ilapper 56 is increased by providing in the end of the barrel or reservoir I0 a cupped tting 64 having a flange 66 which extends peripherally adjacent the flapper 56 as it approaches the port 36. A considerable charge of grease is thus accumulated in the space enclosed by the flange 66, and the paddle 5i), moving into this space in which the grease is more or less confined, operates to force it through the port 36. As indicated in Fig. 2, the flange 66 is U-shaped in outline and its parallel straight 3 portions serve to support the hinge pivot 52 on which the flapper 50 is fulcrumed. The tting 64 includes ears 68 perforated to receive securing screws 69 by which the fitting is attached to the head I4.

Figs. 3 and 4 illustrate the invention as applied to a lubricant compressor in which the reservoir cylinder or barrel 'EEB is disposed with its axis upright and is supported on a base 'l2 which carries the -high pressure cylinder lf3 in a pocket or cavity i6 which extends around the cylinder and communicates therewith through a pair of opposite ports I8, I8. The piston or plunger 88 operating in the cylinder l@ is actuated by a pitman 82 connected to a lever Sil which is fulcrumed at 86 on the base 'E2 and includes an operating arm 88 extending upwardly from the base. In its working stroke the plunger 8i) first covers the ports 'i8 and then forces a charge of grease from the cylinder 'it past the check valve 90 and through the outlet passsage 92.

The upper side of the cavity 'i6 is dened by a rectangular boss ed on the base l2 and the square opening in the boss Sil is matched with a square opening et in the bottom wall e3 of the barrel or reservoir Iii. A square frame lil!) is clamped to the boss by screws 82 with the mar ginal portions of the bottom wall e8 interposed as seen in Fig. 3. A paddle or flapper |530J fits with clearance within the square frame 18! and is hingedly mounted on a pivot lQS secured in lugs 98 of the frame it. A spring Hi! coiled about the pivot 55 rea-cts against the frame and against the upper side of the ilapper HB4 to urge the latter toward the cavity 'i5 and the upper port 18 in the cylinder It.

The plunger 88 is cut away to provide a cam surface H2, and a two-part pin transmits movement from the cam lf2 to the apper i813. One part l I l of the pin is slidably mounted in the wall of the cylinder M and is formed with a tapered tip H5 engaging in the concave end of the pin member HS which is loosely secured by a rivet 26 in the flapper 594i at a short distance from the axis of its pivot it. The push pin is made in two parts primarily for convenience of assembly, but operates substantially like the pin Si) of the structure previously described. On the feeding stroke of the plunger 8@ the cam surface H2 moves the pin lili, H8 upwardly to swing the flapper IM away from the upper port T8 and out of the continuation of the cavity It which is formed by the frame IDG. It will be understood that the barrel or reservoir H3 includes a suitable follower piston which urges the grease downwardly into' the cavity 'F8 and into the space enclosed in the frame lil so that during the return stroke of the plunger SS as the cam surface H2 permits the pin lili, ISG to move downwardly, the spring H0 urges the paddle or apper l@ into the frame HES, pressing and compacting the grease therein and forcing it through the ports 'is into the cylinder lli and tending to break down any voids or air pockets therein in the manner already described.

From the foregoing it will be clear that I have provided a novel improvement in grease guns which includes means operating automatically to disperse air pockets in the grease, and to supplement atmospheric pressure by the provision of additional mechanical pressure for forcing the grease into the cylinder.

While I have shown and described preferred embodiments of my invention, it will be apparent that numerous variations and modifications thereof may be made without departing from the underlying principles of the invention, and I therefore desire by the following claims to include and cover all such Variations and modications by which substantially the results of the invention may be obtained through the use of substantially the same or equivalent means.

I claim:

1. In a grease gun, the combination of a head having a feed cylinder, a plunger reciprocable therein, a barrel secured to the head, said head having a port which connects the interior of said barrel with the cylinder, a follower piston in the barrel, a check valved outlet for the cylinder, a flapper having an area substantially greater than that of the port hingedly mounted adjacent said port for swinging movement of said area toward and from the port, means connected to the plunger for reciprocating said plunger, and means for swinging said ilapper in timed relation to the movement of said plunger.

2. In a grease gun, the combination of a head having a feed cylinder, a plunger reciprocable therein, a barrel secured to the head, said head having a port which connects the interior of said barrel with the cylinder, a follower piston in the barrel, a check valved outlet for the cylinder, a ilapper having a flat surface and hingedly mounted adjacent said port for swinging movementl of said surface to-ward and from the port, means connected to the plunger for reciprocating said plunger, spring means independent of the plunger constantly urging said flapper toward the port, and means actuated intermittently by the stroke of the plunger in one direction to swing the flapper away from said port.

3. In a grease gun, the combination of a head having a feed cylinder, a plunger reciprocable therein, a barrel secured to the head, said head having a port which connects the interior of said barrel with the cylinder, a follower piston in the barrel, a check valved outlet for the cylinder, a apper having an area substantially greater than that of the port hingedly mounted adjacent said port for swinging movement of said area, toward and from the po-rt, means connected to the plunger for reciprocating said plunger, spring means independent of the plunger urging said flapper toward the port, a pin slidable in the head transverse of the cylinder axis with one end engaging the apper and the other end engaging the plunger, said plunger having a cam surface operative through said pin to swing the fiapper away from said port during the feeding stroke of the plunger.

4. In a grease gun, the combinatio-n of a head having a feed cylinder, a plunger reciprocable therein, a barrel secured to the head, said head having a port which connects the interior of said barrel with the cylinder, a follower piston in the barrel, a check valved outlet for the cylinder, a apper of substantial area greater than that of the port hingedly mounted adjacent said port for swinging movement of said area toward and from f the port, means connected to the plunger for reciprocating said plunger, said plunger closing said port in its feeding stroke and expelling grease through the outlet and uncovering said port in its return stroke yielding means urging said apper toward said port during the return stroke of the plunger, and means swinging the flapper away from said port during the feeding stroke of the plunger.

5. In a grease gun, the combination of a head having a feed cylinder, a plunger reciprocable therein, a barrel secured to the head, said head having a port which connects the interiorl of said barrel with the cylinder, a follower piston in the barrel, a check valved outlet for the cylinder, the head including a grease pocket open toward the barrel with said port leading from the pocket into the cylinder, a lapper hingedly mounted for swinging movement into and out of said pocket, the area of the apper approximating the crosssectional area of the pocket, means for reciprocating the plunger, and means operative to swing said ilapper in timed relation to the movement of the plunger.

6. In a grease gun, the combination of a head having a, feed cylinder, a plunger reciprocable therein, a barrel secured to the head, said head -said flapper when the ii'apper is swung toward the port, said lapper moving out of the area embraced by the flange when the fiapper swings away from said port, and means for swinging said ilapper in timed relation to the movement of said plunger.

7. In a grease gun, the combination of a head having a feed cylinder, a plunger reciprocable therein, a grease reservoir adjoining the head,

said head having a pocket and a port leading from said pocket through which port the grease moves from the interior of the reservoir into said cylinder, a check Valved outlet for said cylinder,

means to reciprocate the plunger, a member having an area approximating the cross-sectional area of said pocket and mounted in the reservoir adjacent said port and movable into and out of the pocket for compacting the grease in and around the port, and means for so moving said member when the plunger is reciprocated 8. In a grease gun as dened in claim 7, the means for moving said member comprising yielding means operating independently of the plunger to urge said member into the pocket, and means actuated intermittently by the plunger to move said member out of said pocket.

ERNEST W. DAVIS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,237,189 McCormack et al. Apr. 1, 1941 1,690,058 Davis Oct. 30, 1928 1,894,274 Jacques 1 Jan. 17, 1933 2,062,447 Davis Deo. 1, 1937 FOREIGN PATENTS Number Country Date 623,866 Germany Jan. 7, 1936 

